After a bad night of sleep, we all typically feel distracted and off our mental game. But do you really know all the ways a lack of sleep interferes with your cognitive performance? Most of my patients are surprised to learn just how broadly it affects their ability to think at their best.
It’s difficult to identify a cognitive skill that isn’t affected by sleep and compromised by sleep deprivation. That’s how pervasive the effects of insufficient sleep are on the brain.
Thanks to recent research, we know that sleep deprivation interferes with brain function at a cellular level. A study by scientists at UCLA found that sleep deprivation interferes with the ability of some brain cells to function and communicate with one another. We’ve got billions of neuralcells working on our behalf, enabling us to make decisions, process information, focus on important information—and remember it down the road. Sleep deprivation slows that work down, compromising our mental performance.
Less robust brain-cell activity isn’t the only way poor sleep hampers our ability to think. Other recent discoveries have told us more about how lack of sleep changes brain function and cognitive performance.
disrupts levels of chemicals, including serotonin, dopamine, and cortisol, that affect thought, mood, and energy.
leaves key areas of the brain in an “always on” state of activation.
activates genes that interfere with optimal brain activity.
Because genetic makeup is different from one person to the next, the effects of sleep deprivation on brain function can be, as well—so, some people will experience the negative cognitive and mood effects of sleep deprivation more than others.
We’ve still got much to learn about the full effects of poor and insufficient sleep on cognitive performance and health. But as you’re about to see, what we know already offers many compelling reasons to make getting plenty of sleep a top priority.
You can’t focus well.
Attention is especially sensitive to the effects of sleep deprivation. You know this through experience when you have trouble focusing on tasks after a night of poor sleep. Unfortunately, “a night of poor sleep” is often a series of nights of poor sleep, leading to chronic sleep debt and continually compromised attention.
New research suggests that as many as 75 percent of people with ADHDmay have a chronic, underlying sleep problem stemming from a disruption to their circadian rhythms.
Attention is about focus and concentration—your ability to stay with tasks long enough to make meaningful progress. For most of us, focus is key to both our performance and our sense of purpose, in and away from work. Sleep deprivation makes focus harder to achieve.
Your reaction time slows down.
Attention isn’t only about focusing on big, thought-intensive tasks. It’s also about focusing on—and making sense of—what’s important right now. Remember those sluggish brain cells that result from being sleep deprived? Scientists in that recent study found that sleep deprivation slowed down neural cells’ ability to absorb visual information and translate that visual data into conscious thought. Research shows reaction times are dulled as much by sleeplessness as they are by alcohol.
Reacting to changing circumstances around us is a critical skill that helps keep us—and others—safe. And it can be significantly compromised by sleep deprivation.
You have trouble making—and storing—memories.
Research shows just how important sleep during middle age can be to memory and cognitive health in later years. A new study found that disrupted sleep during middle age, including insomnia, is connected to cognitive decline a decade or more later. (It isn’t just sleeping too little during middle age that is linked to greater risk for cognitive decline later on—the study found sleeping 9 or more hours a night was also associated with later-in-life cognitive problems.)
We know sleep is deeply critical to memory in all its phases—from acquiring memories, to storing them, to recalling them. All phases of memory are complex and involve multiple areas of the brain that are affected by lack of sleep.